ZAMBOANGA CITY -- Investigators are considering the second fatality in Thursday’s powerful blast at an airport here as one of the possible suspects.

Mayor Celso Lobregat said Hatimil Haron Yacob, one of the two persons who died in the bomb attack at Zamboanga International Airport, could be a cohort of Reynaldo Apilado, the construction worker, whom authorities tagged as the “human bomb.”

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Apilado died on the spot when the bomb he was carrying in his backpack exploded near the arrival area of the airport. Yacob expired around 7:40 p.m. Thursday while undergoing medical treatment at a hospital.

Some 24 people, including Sulu Governor Abdusaakur Tan and 69-year-old British national, were injured in the blast, officials said.

The explosion occurred while Tan, along with his son, and other passengers of a Philippine Airlines flight from Manila were exiting the arrival gate of the airport.

The bomb exploded a meter away from the Sulu governor.

Tan told investigators that he was the target of the bombing following an attempt on his life in May 13, 2009 near the provincial capitol of Sulu.

As this developed, Philippine National Police (PNP) Director General Jesus Verzosa asked the military and other intelligence agencies to check possible connection of Thursday’s blast to the bombing incident in Sulu in May last year.

In May 13, 2009, Tan and 10 others were injured when a bomb loaded in a parked motorcycle exploded while the governor's convoy was leaving the provincial capitol grounds in Patikul, Sulu shortly after noontime.

Three of the five suspects in the May 13, 2009 bombing on Tan's convoy are still at large and possibly behind the bombing in Zamboanga on Thursday, Verzosa said.

Verzosa identified the suspects as Temogen Tulawie, Muammar Askali, Sulayman Mohammad Muin, Johan Albani Alihuddin, and a certain Abs.

Tulawie is a former councilor of Jolo town, the capital of Sulu province.

Verzosa said Tulawie, Muin and Abs remain at large while Alihuddin and Askali were arrested in an encounter somewhere in Sulu last year.

The PNP chief said he asked his counterpart in the military to help in the manhunt operations for the three fugitives.

According to police intelligence reports, Tulawie could be hiding in Basilan province and Pagadian City, the capital of Zamboanga del Sur.

Verzosa said the bomb carrier in Zamboanga airport attack has reportedly traveled to Pagadian City last week before he was killed in Zamboanga.

Police are verifying Apilado’s connection with the group, he said.

Western Mindanao Command Benjamin Benjamin Mohammad Dolorfino, meanwhile, vowed to “do everything to help the police expedite the investigation to give justice to the victims.”

He also assured that the Armed Forces of the Philippines will exhaust all means to prevent such lawless violence in ensuing again, as he strongly condemned Thursday's bomb attack.

“The military sees the imperative appeal to the populace to be vigilant at all times stressing that security matters are not just a problem to be solve by the military and the police alone but also a concern of every citizenry, for it is civilian who are often the soft target of this bomb attack,” Dolorfino said.

He said the AFP is now closely working with the police and local officials in the conduct of the investigation to determine the motive of the attack.

The city’s security efforts are now doubled than usual not only in the airport but to include other public places and establishments that are possible target for another attack. (Bong Garcia/Sunnex)